Research Article Vacuum Ultraviolet Field Emission Lamp Consisting of Neodymium Ion Doped Lutetium Fluoride Thin Film as Phosphor Masahiro Yanagihara, 1 Takayuki Tsuji, 1 Mohd Zamri Yusop, 1,2 Masaki Tanemura, 1 Shingo Ono, 1 Tomohito Nagami, 3 Kentaro Fukuda, 3 Toshihisa Suyama, 3 Yuui Yokota, 4 Takayuki Yanagida, 5 and Akira Yoshikawa 4 1 Nagoya Institute of Technology, Gokiso-cho, Showa-ku, Nagoya, Aichi 466-8555, Japan 2 Department of Materials, Manufacturing & Industrial , Faculty of Mechanical Engineering, Universiti Teknologi Malaysia (UTM), 81310 Skudai, Johor, Malaysia 3 Tokuyama Corporation, Kasumigaseki Common Gate West Tower 2-1, Kasumigaseki 3-chome, Chiyoda-ku, Tokyo 100-8983, Japan 4 Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan 5 Kyushu Institute of Technology, 2-4 Hibikino, Wakamatsu-ku, Kitakyushu 808-0196, Japan Correspondence should be addressed to Shingo Ono; ono.shingo@nitech.ac.jp Received 16 July 2014; Accepted 24 August 2014; Published 11 September 2014 Academic Editor: Xiao-Feng Zhao Copyright © 2014 Masahiro Yanagihara et al. his is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. A vacuum ultraviolet (VUV) ield emission lamp was developed by using a neodymium ion doped lutetium luoride (Nd 3+ : LuF 3 ) thin ilm as solid-state phosphor and carbon nanoiber ield electron emitters. he thin ilm was synthesized by pulsed laser deposition and incorporated into the lamp. he cathodoluminescence spectra of the lamp showed multiple emission peaks at 180, 225, and 255 nm. hese emission spectra were in good agreement with the spectra reported for the Nd 3+ : LuF 3 crystal. Moreover, application of an acceleration voltage efectively increased the emission intensity. hese results contribute to the performance enhancement of the lamp operating in the VUV region. 1. Introduction Vacuum ultraviolet (VUV) light has been used in numerous ields, such as cleaning, surface modiication, and steriliza- tion, because short wavelength light with high photon energy is capable of breaking strong chemical bonds [1–3]. herefore, performance improvements of VUV lamps contribute to the progress of these applications. he VUV gas lamp has widely been used [4–6] but presents limited stability, lifetime, and size. VUV lamps using a solid-state phosphor have attracted considerable attention as alternate light sources because they exhibit less deterioration, less luctuation, and higher density than gas lamps [7, 8]. hese lamps require wide band gap materials but few solid-state phosphors have substantial band gaps. Group III nitrides are suitable because they present a direct transition type band structure with a wide band gap [9, 10]. However, even when using AlN, which emits light at a relatively short wavelength, the operating wavelength was limited to deep UV region [9, 11–13]. he wide band gap of diamond can be applied to UV but not to VUV lamps [14]. On the other hand, some luorides have band gaps that are suiciently wide to enable light emission in the VUV region [15, 16]. Fluoride composite materials have been widely studied as laser materials, scintillation materials, and optical materials because of their extremely wide band gap [17– 24]. Speciically, a KMgF 3 thin ilm acting as a solid-state phosphor and carbon nanoiber (CNF) ield electron emitter has previously been incorporated into a VUV lamp [25]. he emission spectra from the lamp showed two emission peaks at 155 and 180 nm in the 140–200 nm wavelength range, showing that solid-state phosphors can be exploited in VUV lamps. Hindawi Publishing Corporation e Scientific World Journal Volume 2014, Article ID 309091, 5 pages http://dx.doi.org/10.1155/2014/309091